Cud-chewing mammal of the family Camelidae, the order Artiodactyla, of which there are two species, the Camelus dromedarius central in North Africa and the Middle East. The other Camelus bactrianus is central to more eastern parts of Asia, and will not be dealt with here.Originally, the camel came from North America some 10 million years ago, where it became extinct about 2 million years ago. All Arabian camels are domesticated from a process that started about 5,000 years ago. Now there are no wild Camelus dromedarius in North Africa and the Middle East.Camelus dromedarius, or Arabian camel, is recognized for its single hump and short hair. The Arabian camel is about 2 metres high and 3 metres long and can weigh up to 700 kg. It has two toes on each foot and thick sole pads, well fitted for crossing hot sand. Moreover, it can close its nostrils as protection against flying sand and its eyes are shielded by long eyelashes. When running, the camel moves both legs on one side in a parallel manner. The camel carries a food reserve in its hump consisting of fatty tissue. The camel can survive on little or no water for long periods, as well as utilize salty vegetation, it can bite off and consume thorny plants living in the desert. Contrary to other mammals, the camel can survive losses of water equalling 25% of its body weight. The urine of the camel is highly concentrated. When the camel finds water, it is capable of consuming enormous quantities. The camel can take extremes in temperatures, both cold and hot, heat primarily because it loses it quickly since all fat is located in the hump on the back.The economic importance of camels has disappeared to a large extent, compared to pre-modern times, when they were used in caravans, for transportation, as well as for its meat and milk. Its wool was used for clothes, and the manure was used for fuel after being dried. In these times, the camel was also a symbol of status and wealth. The modern era has not been able to provide for new forms of usage of the camel and even its meat is considered less appealing than lamb and beef. The total number of camels has diminished, but in countries like Saudi Arabia and United Arab Emirates, the camel is returning as an animal of leisure and hobby. In large areas of Sahara, the camel is still a basis and necessity for human survival.